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Light Timing Study
NCT04753190 · View on ClinicalTrials.gov ↗
Study Summary
Chronic circadian misalignment and sleep restriction peak during late adolescence, and are associated with morning daytime sleepiness, poor academic performance, conduct problems, depressed mood, suicidal ideation, substance use, insulin resistance, and obesity. Bright light exposure from light boxes can shift rhythms earlier (phase advance) to facilitate earlier sleep onset and reduce morning circadian misalignment and the associated risks. To phase advance circadian rhythms, the investigators' PRCs showed that the ideal time to begin light exposure was slightly before wake-up time and light should be avoided around bedtime because this is when light produces maximum phase delay shifts. An unexpected finding from these results, however, was a second advancing region in the afternoon (\~6 to 9 h after habitual wake-up time) suggesting that afternoon light may have more circadian phase advancing ability than traditionally thought. The overall goal of this mechanistic study is to follow-up on the unexpected PRC findings and test whether individually-timed afternoon light alone and in combination with morning bright light can shift circadian rhythms earlier in older adolescents. Four groups will be compared in a randomized parallel group design: afternoon bright light, morning bright light, morning + afternoon bright light, and a dim room light control. Adolescents will complete a 2-week protocol. After a baseline week with a stable sleep schedule, adolescents will live in the laboratory for 7 days. Sleep/dark and the time of bright light exposure will gradually shift earlier. Bright light (\~5000 lux) will be timed individually based on his/her stable baseline sleep schedule. The first 3-h morning bright light exposure will begin 1 h before wake on the first morning. The first 3-h afternoon bright light exposure will begin 5 h after wake. The morning + afternoon exposures will begin at the same times, but each exposure will be 1.5 h so that a total of 3 h of bright li
Conditions Studied
Interventions
- BEHAVIORAL Baseline Sleep Satiation and Phase Stabilization
- BEHAVIORAL Gradually Shifted Sleep
Study Locations (1)
Illinois
- Rush University Medical Center — Chicago
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 113 participants |
| Start Date | 2022-08-22 |
| Est. Completion | 2026-06-30 |
| Phase | NA |
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Full Details on ClinicalTrials.gov ↗What the Registry Record Tells You About NCT04753190
The ClinicalTrials.gov registry entry for NCT04753190 describes a study currently listed as recruiting. It is categorized as NA, which is the standard way researchers label where a study sits along the investigational pathway from early safety work through later efficacy and post-marketing evaluation. The registered enrollment target is 113 participants, a figure that helps gauge the scale of data the investigators plan to collect. The listed sponsor is Rush University Medical Center, which has 168 total studies on file at ClinicalTrials.gov, and sponsors are the parties responsible for study design, oversight, and regulatory filings.
The record links to 5 conditions, with Sleep appearing as the primary indexed condition, and to 2 interventions — of which Baseline Sleep Satiation and Phase Stabilization is the first listed. Interventions can include drugs, devices, procedures, behavioral programs, or observational arms, and each is tracked as a separate registry field so that downstream queries can filter accurately. When a trial lists multiple interventions, it usually reflects a multi-arm design or a comparison protocol rather than a single treatment being tested in isolation. The brief summary published in the registry is the clearest source of protocol intent and should be read before drawing conclusions from any sidebar tags.
Geographic footprint matters for practical reasons: NCT04753190 reports 1 study location spanning 1 distinct geographic area — top geographies include Illinois. A larger site network tends to correlate with broader recruitment capacity, but it does not imply anything about study quality, and site-level enrollment status can diverge from the overall registry status shown above. Every data point on this page comes from the public ClinicalTrials.gov dataset and is reproduced here for reference only; it is not a medical recommendation, an endorsement of the sponsor, or an invitation to enroll. Verify current status, eligibility criteria, and contact details directly at ClinicalTrials.gov, and discuss any participation decision with your own healthcare provider.
Frequently Asked Questions
What is clinical trial NCT04753190 about?
NCT04753190 is a clinical study titled "Light Timing Study". Chronic circadian misalignment and sleep restriction peak during late adolescence, and are associated with morning daytime sleepiness, poor academic performance, conduct problems, depressed mood, suicidal ideation, substance use, insulin resistance, and obesity. Bright light exposure from light boxe...
What is the current status of trial NCT04753190?
This trial is currently recruiting. It is a NA study. The enrollment target is 113 participants. The study started on 2022-08-22. Estimated completion is 2026-06-30.
What conditions does trial NCT04753190 study?
This clinical trial studies the following conditions: Sleep, Circadian Rhythm, Adolescence, Light, Chronobiology. These conditions were identified from the trial registry and reflect the primary focus areas of the research.
What interventions are being tested in trial NCT04753190?
The interventions under investigation include: Baseline Sleep Satiation and Phase Stabilization (BEHAVIORAL), Gradually Shifted Sleep (BEHAVIORAL). Each intervention is being evaluated for safety and efficacy as part of this clinical study.
Who is sponsoring clinical trial NCT04753190?
This trial is sponsored by Rush University Medical Center, which has 168 total clinical trials registered on ClinicalTrials.gov. The sponsor is responsible for the study's design, funding, and regulatory compliance.
Where is trial NCT04753190 being conducted?
This trial has 1 study location across Illinois. Contact the study sites directly through ClinicalTrials.gov for enrollment availability.
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